Wednesday, October 01, 2008

Releases, Bugs, and the iphone

Sometimes I have one of those weeks where all I do is look at crashes and weird behavior. This is turning into one of those weeks. So here's some status on the various bugs floating around.

I should say: you'll find a lot of developers blaming the technology providers for bugs (just look at how many OpenGL developers have blamed ATI for their apps crashing). Sometimes it's the app, sometimes it's the driver. More importantly:

You don't know who's fault it is until you fully understand the bug.

The fix for a bug might not be in the broken code. That is, one piece of code can work around a bug in another.

So...you can't necessarily tell whose fault it was from new drivers coming out, us changing the sim, etc. But...when it's my stupid code, I'll admit it openly - no one should think that a bunch of other smart programmers are screwing up on my behalf. (This is also useful to other apps developers, who can know that my bug isn't the same as their bug, since my bug was in my code.)

X-Plane: we're happy with 921r2 finally...the final bug (crash on startup on the Mac) was due to an incompatibility between Apple's OpenAL implementation and special memory allocator (which is really just a wrapper around NEDMalloc). I still don't know exactly what the rules should be (you try reading the C++ spec!) but for now we turned the allocator off on Mac.

(This brings up another issue about bugs - you can't tell whose bug it is by whose code crashes, since one piece of code can sabotage another.)

So the next X-Plane release will probably be 930, with new features. We may have a few more language patches if needed.

iPhone: the 9.01 iPhone patch is out, and it improves framerate a bit. We are still seeing crashes on startup for users who have just downloaded the app. Rebooting the phone will fix this, but please see this post for more info! We need your help to collect more data.

Radeon 9800 on Windows: for the longest time we've had users reporting "framebuffer incomplete" errors when using catalyst 8.x drivers, an R300 chipset, and Windows with X-Plane 9.x. I have been trying to reproduce this problem "in the lab" off and on for months, but finally saw it this week. From what I can tell, we're getting into some low-memory condition and the driver is freaking out in various ways. The command line options people sometimes use to get past this are probably rearranging memory, not saving it. I don't know why the Catalyst 7.x drivers don't have this problem. But...at least I am making more progress than I was before. Please see this post for more info.

Installers: I am working on the 2.05 installer. I have seen a number of users report problems running a full install from DVDs, so I am just starting to investigate that. I will post more when I have something to test. Unfortunately the problems reported are not something we see here.